1. Field of the Invention
The present invention relates to a percussion hand-held power tool such as chisel hammer or combination hammer and having a contactless manual switch located in the tool side handle.
2. Description of the Prior Art
In electrical hand-held power tools which are subjected, because of their intended use, to both high dust load and strong vibrations, mechanical contact switches undergo excessive wear.
U.S. Pat. No. 5,014,793 discloses an electrical hand-held power tool that is controlled by a manual switch actuation means of which actuates mechanical piezosensors for controlling a power switch. The pressure sensors are necessarily arranged in a mechanical contact with the actuation means. Therefore, the vibrations are transmitted to the actuation means.
German Publication DE 199 42 156 discloses a combination hammer having a contactless rotary switch which is associated, in a control manner, with a Hall sensor switch with which it is connected by a displaceable switching rod with a permanent magnet. As both the Hall sensor switch and the rotary actuation means are connected with one and the same housing, there are no relative vibrations that can adversely affect the switching process.
German Publication DE 102 59 569 discloses an electrical hand-held power tool having a vibrating assembly that vibrates along a vibration axis, a contactless electrical manual switch with actuation means located in a vibration decoupled main handle, and a sensor switch. The sensor switch is connected vibration-free with a switching means carrier with a permanent magnet The switching means carrier is pivotable in the direction transverse to the vibration axis by pivotal movement transmitting means axially displaceable along the vibration axis within certain limits in response to a manual actuation of the actuation means. This solution is cannot be used in power tools with a side vibration-decoupled handle that extends transverse to the vibration axis.
Japanese Publication JP 200279477 discloses an electrical hand-held power tool having an assembly vibrating along a vibration axis, two, extending transverse to the vibration axis, vibration-decoupled, side handles pivotal about a handle pivot point, and a manual switch with axially actuatable actuation means and provided on one of the handles.
An object of the present invention is an electrical hand-held power tool having a contactless electrical manual switch in a side handle and which is insensitive to vibrations.